Brimonidine Tartrate

Why eye pressure climbs

Fluid is made continuously inside the front of the eye and leaves through a mesh of tissue at the edge of the iris. When that drain is sluggish, the volume builds and the pressure against the optic nerve — the cable of fibres carrying sight signals to the brain — climbs with it. Open-angle glaucoma, and ocular hypertension (a reading above the usual range with no other sign of damage), are the two conditions these drops are used for.

Brimonidine tartrate is an alpha-2 agonist. It docks onto receptors on the nerves within the eye and turns down the chemical messages that keep fluid production going, and it widens the uveoscleral pathway, a drainage channel running through the eye wall. Two sides of the same problem, then, worked on at once.

Combigan, the one listing here

Combigan is what this page carries: a 0.2/0.5% eye drop in a bottle, filed in the eye care range. Two actives share it. Brimonidine tartrate supplies the 0.2%; timolol maleate, a beta-blocker that also restrains the eye's fluid production, supplies the 0.5%. One bottle lowers pressure by two routes, which is why the strength is written as a pair of numbers rather than a single figure.

Putting the drops in

Combigan goes in twice a day, morning and evening — one drop into each eye that needs treatment. Pull the lower lid away to make a gap, aim the nozzle at it and release a single drop, touching nothing with the tip. Then shut the eye and press gently at the inner corner, beside the nose, for about a minute, so less of the drop escapes down the tear duct. If another eye drop is part of your routine, leave several minutes between the two.

Expect a brief sting when the drop lands. Some people get a dry mouth or feel sleepy afterwards, so see how you react before driving.

Side effects and interactions

Redness, itching, a gritty feeling and short spells of blurred vision are the usual local complaints, and they often ease as the eye gets used to the drops. A second pattern can start much later: weeks or months into treatment, the eyes and eyelids turn red, itchy and puffy.

Timolol is the ingredient that travels beyond the eye. Small amounts reach the bloodstream, where they can slow the pulse and narrow the airways, which is why asthma and some heart-rhythm problems rule it out. Brimonidine is not used with MAO inhibitors, an older class of antidepressant, and sedatives or alcohol add to its drowsiness. Swelling of the face or eyelids, or trouble breathing, is a severe allergic reaction and needs emergency treatment.